Process for synthesis of ethylene polymers

A non-cryogenic process for synthesis of disentangled ultra high molecular weight polyethylene (DUHMWPE) having a molecular weight in the range of 0.08 million g/mole to 15 million g/mole, said process comprising the following steps:

• a) mixing FI catalyst of Formula I
• with a hydrocarbon solvent containing poly-methyl aluminoxane (P-MAO) co-catalyst, wherein the molar ratio of the amount of co-catalyst and the amount of FI catalyst is in the range of 100 to 200, in a vessel under stirring before polymerization or directly in the polymerization vessel at a temperature ranging between 25° C. and 29° C. under a dry nitrogen atmosphere;
• and
• b. introducing ethylene in the polymerization vessel to attain a pressure in the range of 1 bar to 2.5 bar and polymerizing ethylene for a predetermined time in a solution or a suspension, continuously or batch wise, in one or more stages at a temperature in the range of 30° C. to 50° C.